Democratic Sen. Mary Landrieu kicked off her re-election campaign in Louisiana with a television ad criticizing President Obama's troubled health care law, an early indication of just how important some vulnerable Democrats fear the issue will be in next fall's elections.

Landrieu supports the law, and has staked a share of her reputation on its success. Still, her opening shot of the campaign zeroed in on its problems and emphasized her efforts to blunt its impact on the public.

The ad alludes to legislation Landrieu introduced that would allow millions of people to renew existing health plans that were cancelled despite Obama's pledge that they wouldn't be.

"This is a promise you made, this is a promise you should keep," Landrieu says in the ad, referring to Obama's broken promise that "If you like your plan, you can keep it."

Landrieu's legislation is presented in the ad as the catalyst for changes made to Obamacare. But her bill never came up for a vote. Instead, the White House, facing a national outcry over the cancellation of millions of existing plans, agreed to let people keep those plans for a year, though not permanently as Landrieu proposed.

The National Republican Senatorial Committee called Landrieu's spot "the most disingenuous ad of the year."

Obama approval ratings hit record low 

President Obama's disapproval ratings have hit record levels with Americans who remain concerned about the botched rollout of Obamacare despite the president's reassurances that it is being fixed.

More than half of those surveyed — 54 percent — now disapprove of the job the president is doing, the Wall Street Journal/NBC poll found. Just 43 percent approve.

The poll finds health care more than any other issue responsible for Obama's slide. Fifty-eight percent said Obamacare is the issue that most shaped their views of the president this past year. Just 25 percent cited the economy and 23 percent pointed to the government shutdown.

Obamacare's rocky rollout deeply damaged the public's perception of Obama’s trustworthiness and managerial skills. Just 39 percent say Obama demonstrates “strong leadership qualities,” a 14 percentage point drop from 53 percent at the beginning of the year.

The one bright spot for the White House is that even though the president is at his lowest point, the public still likes him more than Congress. Nearly eight in 10 — 79 percent — viewed this Congress as one of the worst ever.

John Cornyn gets challenger in Texas GOP primary

Republican Sen. John Cornyn of Texas was just waiting for someone to challenge him in 2014. He prepared by building a war chest of nearly $7 million and spearheading a “Keep Texas Red” campaign that promoted Republicans statewide.

Just when it appeared that Cornyn had scared off all would-be challengers, though, Rep. Steve Stockman stepped in at the very last minute to challenge Cornyn in next year's Republican primary, asserting that the incumbent wasn't conservative enough.

But it's not exactly the challenge Cornyn feared.

Stockman has a record of making controversial remarks that could haunt him in a statewide race. His campaign is in debt with little or no new money pouring in. And the outside conservative groups that are bankrolling conservative challengers to Republican incumbents elsewhere were quick to announce that they wouldn't help Stockman.

"Stockman has taken absolutely no steps to prepare for his own re-election, let alone a statewide campaign of this magnitude," said one Republican strategist with ties to Cornyn. "He doesn't even have enough money to run radio ads in his own district, let alone a state with 23 media markets in a ... primary that's less than three months away."